Hole in bathroom wall

[Mluk]

Hello, hope I've posted this in the right place.

I've got a hole in my bathroom wall behind the tiles which I'd like to try and patch myself. It appears as though it's a layer of cement onto brick and the old cement is now just powder, anyone know what I could use to patch this?

Any help is much appreciated,

Thanks.

 

[roy c]

Scrape all old dusty material off the area and brush it over with some water. Let it dry off and then get some tile adhesive and spread it all over the area and you should be able to level out to existing area. then leave it to harden, Then you are good to tile over it all..